1. Field of the Invention
The present invention relates to a method and apparatus for singling sheet material, in particular papers of value such as bank notes, checks, etc., for subsequent processing of single pieces of sheet material.
2. Description of the Background Art
Sheet material, e.g. bank notes, are usually processed using bank note processing machines wherein the bank notes are inserted into an input pocket in a stack. The input pocket is connected with a singler that singles the bank notes present in a stack and transfers them singly to a transport system. The transport system then transports the single bank notes e.g. past sensors for e.g. counting, recognizing and checking the state and authenticity of the bank notes. In dependence on the check results the single bank notes can finally be sorted into different output pockets.
Problems in processing can always arise when errors occur in the singling of the bank notes. A well-known error of this kind is the so-called double pick. Instead of a single bank note, two or more bank notes are grasped by the singler and transferred to the transport system. Errors of this kind can be recognized without any great problems by determining the thickness of the singled bank notes. If the determined thickness exceeds a predetermined threshold value, it is recognized that more than one bank note was singled. Greater problems result when the error involves a mix-up of the singling order. In this case the bank note to be singled next is not singled, but a bank note disposed after said note in the stack of bank notes inserted into the input pocket. A mix-up of singling order is problematic within a stack of bank notes in particular in the processing of different groups of bank notes separated from each other by separation or header cards. In this case a mix-up of singling order can lead to bank notes being erroneously attributed to the wrong group of bank notes.
The problem of the present invention is therefore to specify a method and apparatus for singling sheet material, in particular papers of value such as bank notes, checks, etc., for subsequent processing of single pieces of sheet material wherein mix-ups of the singling order can be recognized.
The invention starts out from the consideration that singling order is always maintained when at the place of singling it is checked whether the piece of sheet material to be singled next is singled.
The advantage of the invention is to be seen in particular in that it permits problems to be avoided that result from a mix-up of singling order. Such mix-ups are problematic in particular in the processing of different groups of bank notes by means of separation cards since in this case the single groups of bank notes are accounted for incorrectly.
In a development it is provided that monitoring of the singling order is effected by checking a motion of the next piece of sheet material to be singled.
The advantage of the development is to be seen in particular in that monitoring the motion of the next piece of sheet material to be singled permits an especially simple realization of the monitoring of singling order.
The figures show only the components essential in connection with the present invention. Similar components of the figures are marked by the same reference signs.